No duplicate names rule proposal

[danielriedmueller]

No Duplicate Names (no-duplicate-names)

A rule that checks, whether two elements have the same name.

Example of incorrect usage for this rule:

    ...
    <bpmn:startEvent id="StartEvent_070f514" name="Element A">
      <bpmn:outgoing>Flow_1fnaiy8</bpmn:outgoing>
    </bpmn:startEvent>
    <bpmn:endEvent id="Event_1copj14" name="Element A">
      <bpmn:incoming>Flow_1fnaiy8</bpmn:incoming>
    </bpmn:endEvent>
    ...

Example of correct usage for this rule:

    ...
    <bpmn:startEvent id="StartEvent_070f514" name="Element A">
      <bpmn:outgoing>Flow_1fnaiy8</bpmn:outgoing>
    </bpmn:startEvent>
    <bpmn:endEvent id="Event_1copj14" name="Element B">
      <bpmn:incoming>Flow_1fnaiy8</bpmn:incoming>
    </bpmn:endEvent>
    ...

How does the rule improve the BPMN diagram?

With unique named elements, each element could be recognized by a human (IDs are not human friendly readable) and for further processing, like unique description pages for each element with nice titles.

Rule Details

• Name: no-duplicate-names
• Default notification level: error

What alternatives did you consider?

In our project, we need to have each elements name be unique. The unique ids are not human friendly readable.
Alternative would be to auto rename name, if same name already exists (this would be the workaround in our project).
Our project if you are interested: https://www.mediawiki.org/wiki/Extension:Cognitive_Process_Designer

[nikku]

I think this is a great proposal for a rule, thanks for sharing 🤩

[barmac]

While the rule may be useful, I'd rather not include it in the recommended ruleset. There can be multiple exceptions, e.g. for outcoming flows of an exclusive gateway:

[nikku]

I think we'd be just fine if we whitelist outgoing flows.

[nikku]

We also want to whitelist labels on gateways and throw events:

[barmac]

I am moving this to the backlog now, but we can revisit and/or gather more exceptions from this rule.